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Despite a theory that an imbalance in goal-directed versus habitual systems serve as building blocks of compulsions, research has yet to delineate how this occurs during arbitration between the two systems in obsessive-compulsive disorder. Inspired by a brain model in which the inferior frontal cortex selectively gates the putamen to guide goal-directed or habitual actions, this study aimed to examine whether disruptions in the arbitration process via the fronto-striatal circuit would underlie imbalanced decision-making and compulsions in patients. Thirty patients with obsessive-compulsive disorder [mean (standard deviation) age = 26.93 (6.23) years, 12 females (40%)] and 30 healthy controls [mean (standard deviation) age = 24.97 (4.72) years, 17 females (57%)] underwent functional MRI scans while performing the two-step Markov decision task, which was designed to dissociate goal-directed behaviour from habitual behaviour. We employed a neurocomputational model to account for an uncertainty-based arbitration process, in which a prefrontal arbitrator (i.e. inferior frontal gyrus) allocates behavioural control to a more reliable strategy by selectively gating the putamen. We analysed group differences in the neural estimates of uncertainty of each strategy. We also compared the psychophysiological interaction effects of system preference (goal-directed versus habitual) on fronto-striatal coupling between groups. We examined the correlation between compulsivity score and the neural activity and connectivity involved in the arbitration process. The computational model captured the subjects' preferences between the strategies. Compared with healthy controls, patients had a stronger preference for the habitual system (t = -2.88, P = 0.006), which was attributed to a more uncertain goal-directed system (t = 2.72, P = 0.009). Before the allocation of controls, patients exhibited hypoactivity in the inferior frontal gyrus compared with healthy controls when this region tracked the inverse of uncertainty (i.e. reliability) of goal-directed behaviour (P = 0.001, family-wise error rate corrected). When reorienting behaviours to reach specific goals, patients exhibited weaker right ipsilateral ventrolateral prefronto-putamen coupling than healthy controls (P = 0.001, family-wise error rate corrected). This hypoconnectivity was correlated with more severe compulsivity (r = -0.57, P = 0.002). Our findings suggest that the attenuated top-down control of the putamen by the prefrontal arbitrator underlies compulsivity in obsessive-compulsive disorder. Enhancing fronto-striatal connectivity may be a potential neurotherapeutic approach for compulsivity and adaptive decision-making.
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Tomada de Decisões , Objetivos , Imageamento por Ressonância Magnética , Transtorno Obsessivo-Compulsivo , Humanos , Feminino , Adulto , Masculino , Imageamento por Ressonância Magnética/métodos , Transtorno Obsessivo-Compulsivo/fisiopatologia , Transtorno Obsessivo-Compulsivo/diagnóstico por imagem , Transtorno Obsessivo-Compulsivo/psicologia , Incerteza , Tomada de Decisões/fisiologia , Adulto Jovem , Modelos Neurológicos , Comportamento Compulsivo/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Córtex Pré-Frontal/diagnóstico por imagem , Putamen/fisiopatologia , Putamen/diagnóstico por imagem , Encéfalo/fisiopatologia , Encéfalo/diagnóstico por imagem , Simulação por ComputadorRESUMO
BACKGROUND: Impaired cognitive reappraisal is a notable symptom of early psychosis, but its neurobiological basis remains underexplored. We aimed to identify the underlying neurobiological mechanism of this impairment by using resting-state functional connectivity (FC) analyses focused on brain regions related to cognitive reappraisal. METHODS: Resting-state functional magnetic resonance images were collected from 36 first-episode psychosis (FEP) patients, 32 clinical high-risk (CHR) individuals, and 48 healthy controls (HCs). Whole-brain FC maps using seed regions associated with cognitive reappraisal were generated and compared across the FEP, CHR and HC groups. We assessed the correlation between resting-state FC, reappraisal success ratio, positive symptom severity and social functioning controlling for covariates. RESULTS: FEP patients showed higher FC between the left superior parietal lobe and left inferior frontal gyrus than HCs. Higher FC between the left superior parietal lobe and left inferior frontal gyrus negatively correlated with the reappraisal success ratio in the FEP group after controlling for covariates. Lower FC correlated with lower positive symptom severity and improved global functioning in the FEP group. CONCLUSIONS: Alteration in left frontoparietal connectivity reflects impaired cognitive reappraisal in early psychosis, and such alteration correlates with increased positive symptoms and decreased global functioning. These findings offer a potential path for interventions targeting newly emerging symptoms in the early stages of psychosis.
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Lobo Frontal , Imageamento por Ressonância Magnética , Lobo Parietal , Transtornos Psicóticos , Humanos , Transtornos Psicóticos/fisiopatologia , Transtornos Psicóticos/diagnóstico por imagem , Masculino , Feminino , Lobo Parietal/fisiopatologia , Lobo Parietal/diagnóstico por imagem , Adulto Jovem , Adulto , Lobo Frontal/fisiopatologia , Lobo Frontal/diagnóstico por imagem , Adolescente , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Conectoma , Mapeamento EncefálicoRESUMO
Changes in dopamine and fronto-striato-thalamic (FST) circuit functional connectivity are prominent in schizophrenia. Dopamine is thought to underlie connectivity changes, but experimental evidence for this hypothesis is lacking. Previous studies examined the association in some of the connections using positron emission tomography (PET) and functional MRI (fMRI); however, PET has disadvantages in scanning patients, such as invasiveness. Excessive dopamine induces neuromelanin (NM) accumulation, and NM-MRI is suggested as a noninvasive proxy measure of dopamine function. We aimed to investigate the association between NM and FST circuit connectivity at the network level in patients with schizophrenia. We analysed substantia nigra NM-MRI and resting-state fMRI data from 29 schizophrenia patients and 63 age- and sex-matched healthy controls (HCs). We identified the FST subnetwork with abnormal connectivity found in schizophrenia patients compared to that of HCs and investigated the relationship between constituting connectivity and NM-MRI signal. We found a higher NM signal (t = -2.12, p = 0.037) and a hypoconnected FST subnetwork (FWER-corrected p = 0.014) in schizophrenia patients than in HCs. In the hypoconnected subnetwork of schizophrenia patients, lower left supplementary motor area-left caudate connectivity was associated with a higher NM signal (ß = -0.38, p = 0.042). We demonstrated the association between NM and FST circuit connectivity. Considering that the NM-MRI signal reflects dopamine function, our results suggest that dopamine underlies changes in FST circuit connectivity, which supports the dopamine hypothesis. In addition, this study reveals implications for the future use of NM-MRI in investigations of the dopamine system.
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Evidence indicating abnormal functional connectivity (FC) among the cortex, thalamus, and cerebellum in schizophrenia patients has increased. However, the role of the thalamus and cerebellum when integrated into intrinsic networks and how those integrated networks interact in schizophrenia patients are largely unknown. We generated an integrative network map by merging thalamic and cerebellar network maps, which were parcellated using a winner-take-all approach, onto a cortical network map. Using cognitive networks, the default mode network (DMN), the dorsal attention network (DAN), the salience network (SAL), and the central executive network (CEN) as regions of interest, the FC of 48 schizophrenia patients was compared with that of 57 healthy controls (HCs). The association between abnormal FC and cognitive impairment was also investigated in patients. FC was lower between the SAL-CEN, SAL-DMN, and DMN-CEN and within-CEN in schizophrenia patients than in HCs. Hypoconnectivity between the DMN-CEN was correlated with impaired cognition in schizophrenia patients. Our findings broadly suggest the plausible role of the thalamus and cerebellum in integrative intrinsic networks in patients, which may contribute to the disrupted triple network and cognitive dysmetria in schizophrenia.
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BACKGROUND AND HYPOTHESIS: Aberrant thalamocortical connectivity and large-scale network interactions among the default mode network (DMN), salience network (SN), and executive control network (ECN) (ie, triple networks) have been regarded as critical in schizophrenia pathophysiology. Despite the importance of network properties and the role of the thalamus as an integrative hub, large-scale thalamocortical triple network functional connectivities (FCs) in different stages of the psychotic disorder have not yet been reported. STUDY DESIGN: Thirty-nine first-episode psychosis (FEP) patients, 75 individuals at clinical high risk (CHR) for psychosis, 46 unaffected relatives (URs) of schizophrenia patients with high genetic loading, and 110 healthy controls (HCs) underwent resting-state functional magnetic resonance imaging (rs-fMRI). Modular community detection was used to identify cortical and thalamic resting-state networks, and thalamocortical network interactions were compared across the groups. STUDY RESULTS: Thalamic triple networks included higher-order thalamic nuclei. Thalamic SN-cortical ECN FC was greater in the FEP group than in the CHR, UR, and HC groups. Thalamic DMN-cortical DMN and thalamic SN-cortical DMN FCs were greater in FEP and CHR participants. Thalamic ECN-cortical DMN and thalamic ECN-cortical SN FCs were greater in FEP patients and URs. CONCLUSIONS: These results highlight critical modulatory functions of thalamic triple networks and the shared and distinct patterns of thalamocortical triple network dysconnectivities across different stages of psychotic disorders. The current study findings suggest that large-scale thalamocortical triple network dysconnectivities may be used as an integrative biomarker for extending our understanding of the psychosis pathophysiology and for targeting network-based neuromodulation therapeutics.
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Transtornos Psicóticos , Esquizofrenia , Humanos , Imageamento por Ressonância Magnética , Transtornos Psicóticos/diagnóstico por imagem , Esquizofrenia/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Vias Neurais/diagnóstico por imagem , Mapeamento Encefálico/métodosRESUMO
BACKGROUND: Identifying more homogenous subtypes of patients with obsessive-compulsive disorder (OCD) using biological evidence is critical for understanding complexities of the disorder in this heterogeneous population. Age of onset serves as a useful subtyping scheme for distinguishing OCD into two subgroups that aligns with neurodevelopmental perspectives. The underlying neurobiological markers for these distinct neurodevelopmental differences can be identified by investigating gyrification changes to establish biological evidence-based homogeneous subtypes. METHODS: We compared whole-brain cortical gyrification in 84 patients with early-onset OCD, 84 patients with late-onset OCD, and 152 healthy controls (HCs) to identify potential markers for early neurodevelopmental deficits using the local gyrification index (lGI). Then, the relationships between lGI in clusters showing significant differences and performance in visuospatial memory and verbal fluency, which are considered trait-related neurocognitive impairments in OCD, were further examined in early-onset OCD patients. RESULTS: The early-onset OCD patients exhibited significantly greater gyrification than those with late-onset OCD patients and HCs in frontoparietal and cingulate regions, including the bilateral precentral, postcentral, precuneus, paracentral, posterior cingulate, superior frontal, and caudal anterior cingulate gyri. Moreover, impaired neurocognitive functions in early-onset OCD patients were correlated with increased gyrification. CONCLUSIONS: Our findings provide a neurobiological marker to distinguish the OCD population into more neurodevelopmentally homogeneous subtypes, which may contribute to the understanding of the neurodevelopmental underpinnings of an etiology in early-onset OCD consistent with the accumulated phenotypic evidence of greater neurodevelopmental deficits in early-onset OCD than in late-onset OCD.
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Transtorno Obsessivo-Compulsivo , Humanos , Transtorno Obsessivo-Compulsivo/diagnóstico por imagem , Transtorno Obsessivo-Compulsivo/epidemiologia , Lobo Parietal , Encéfalo , Giro do Cíngulo/diagnóstico por imagem , Fenótipo , Transtornos de Início Tardio , Imageamento por Ressonância MagnéticaRESUMO
BACKGROUND: Prognostic heterogeneity in early psychosis patients yields significant difficulties in determining the degree and duration of early intervention; this heterogeneity highlights the need for prognostic biomarkers. Although mismatch negativity (MMN) has been widely studied across early phases of psychotic disorders, its potential as a common prognostic biomarker in early periods, such as clinical high risk (CHR) for psychosis and first-episode psychosis (FEP), has not been fully studied. METHODS: A total of 104 FEP patients, 102 CHR individuals, and 107 healthy controls (HCs) participated in baseline MMN recording. Clinical outcomes were assessed; 17 FEP patients were treatment resistant, 73 FEP patients were nonresistant, 56 CHR individuals were nonremitters (15 transitioned to a psychotic disorder), and 22 CHR subjects were remitters. Baseline MMN amplitudes were compared across clinical outcome groups and tested for utility prognostic biomarkers using binary logistic regression. RESULTS: MMN amplitudes were greatest in HCs, intermediate in CHR subjects, and smallest in FEP patients. In the clinical outcome groups, MMN amplitudes were reduced from the baseline in both FEP and CHR patients with poor prognostic trajectories. Reduced baseline MMN amplitudes were a significant predictor of later treatment resistance in FEP patients [Exp(ß) = 2.100, 95% confidence interval (CI) 1.104-3.993, p = 0.024] and nonremission in CHR individuals [Exp(ß) = 1.898, 95% CI 1.065-3.374, p = 0.030]. CONCLUSIONS: These findings suggest that MMN could be used as a common prognostic biomarker across early psychosis periods, which will aid clinical decisions for early intervention.
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Transtornos Psicóticos , Esquizofrenia , Humanos , Prognóstico , Eletroencefalografia , Modelos Logísticos , BiomarcadoresRESUMO
Maladaptive habitual behaviours of obsessive-compulsive disorder are characterized by cognitive inflexibility, which hypothetically arises from dysfunctions of a certain cortico-basal ganglia-thalamo-cortical circuit including the ventrolateral prefrontal region. Inside this neurocircuit, an imbalance between distinct striatal projections to basal ganglia output nuclei, either directly or indirectly via the external globus pallidus, is suggested to be relevant for impaired arbitration between facilitation and inhibition of cortically initiated activity. However, current evidence of individually altered cortico-striatal or thalamo-cortical connectivities is insufficient to understand how cortical dysconnections are linked to the imbalanced basal ganglia system in patients. In this study, we aimed to identify aberrant ventrolateral prefronto-basal ganglia-thalamic subnetworks representing direct-indirect imbalance and its association with cognitive inflexibility in patients. To increase network detection sensitivity, we constructed a cortico-basal ganglia-thalamo-cortical network model incorporating striatal, pallidal and thalamic subregions defined by unsupervised clustering in 105 medication-free patients with obsessive-compulsive disorder (age = 25.05 ± 6.55 years, male/female = 70/35) and 99 healthy controls (age = 23.93 ± 5.80 years, male/female = 64/35). By using the network-based statistic method, we analysed group differences in subnetworks formed by suprathreshold dysconnectivities. Using linear regression models, we tested subnetwork dysconnectivity effects on symptom severity and set-shifting performance assessed by well-validated clinical and cognitive tests. Compared with the healthy controls, patients were slower to track the Part B sequence of the Trail Making Test when the effects of psychomotor and visuospatial functions were adjusted (t = 3.89, P < 0.001) and made more extradimensional shift errors (t = 4.09, P < 0.001). In addition to reduced fronto-striatal and striato-external pallidal connectivities and hypoconnected striato-thalamic subnetwork [P = 0.001, family-wise error rate (FWER) corrected], patients had hyperconnected fronto-external pallidal (P = 0.012, FWER corrected) and intra-thalamic (P = 0.015, FWER corrected) subnetworks compared with the healthy controls. Among the patients, the fronto-pallidal subnetwork alteration, especially ventrolateral prefronto-external globus pallidal hyperconnectivity, was associated with relatively fewer extradimensional shifting errors (ß = -0.30, P = 0.001). Our findings suggest that the hyperconnected fronto-external pallidal subnetwork may have an opposite effect to the imbalance caused by the reduced indirect pathway (fronto-striato-external pallidal) connectivities in patients. This ventrolateral prefrontal hyperconnectivity may help the external globus pallidus disinhibit basal ganglia output nuclei, which results in behavioural inhibition, so as to compensate for the impaired set shifting. We suggest the ventrolateral prefrontal and external globus pallidus as neuromodulatory targets for inflexible habitual behaviours in obsessive-compulsive disorder.
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Globo Pálido , Transtorno Obsessivo-Compulsivo , Adolescente , Adulto , Gânglios da Base , Corpo Estriado , Feminino , Globo Pálido/fisiologia , Humanos , Masculino , Vias Neurais/fisiologia , Adulto JovemRESUMO
BACKGROUND: Hippocampal volume changes have been reported in schizophrenia patients and their relatives and are proposed to contribute to the pathophysiology of schizophrenia. However, volume changes in the total hippocampus have not been consistently reported in relatives. The hippocampus consists of multiple subregions, and based on previous inconsistent results, subtle changes in specific subregions may occur in relatives. Here, we examined the subregion volumes in unaffected, high-functioning relatives (URs) without any psychiatric symptoms with high genetic loading with at least one first-degree relative diagnosed with schizophrenia and at least one or more other affected first- to third-degree relatives. METHODS: We acquired structural magnetic resonance imaging data from 50 URs, 101 first-episode psychosis (FEP) patients, and 101 healthy controls (HCs). The cornu ammonis (CA), dentate gyrus, and subiculum subfields were automatically segmented using FreeSurfer 7.1.0. Each subregion volume was compared across the groups. RESULTS: Compared with the HCs, the URs had a significant volume reduction in the left anterior CA (p = 0.039, Cohen's d = 0.480). In addition, the URs had a significantly larger right posterior subiculum (p = 0.001, Cohen's d = 0.541) than the FEP. CONCLUSIONS: The smaller left anterior CA in the URs may reflect their genetic vulnerability to schizophrenia and supports previous findings suggesting specific vulnerability in this region. The volume differences between the URs and FEP patients in the right posterior subiculum may suggest that a smaller volume in this region may reflect a risk for schizophrenia other than genetic vulnerability.
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Transtornos Psicóticos , Esquizofrenia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Tamanho do Órgão , Transtornos Psicóticos/diagnóstico por imagem , Transtornos Psicóticos/genética , Transtornos Psicóticos/patologia , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/genética , Esquizofrenia/patologiaRESUMO
OBJECTIVE: In the triple-network model, the salience network (SN) plays a crucial role in switching between the default-mode network (DMN) and the central executive network (CEN). Aberrant patterns of triple-network connectivity have been reported in schizophrenia patients, while findings have been less consistent for patients in the early stages of psychotic disorders. Thus, the present study examined the connectivity among the SN, DMN, and CEN in first-episode psychosis (FEP) patients and individuals at clinical high risk (CHR) for psychosis. METHODS: Thirty-nine patients with FEP, 78 patients with CHR for psychosis, and 110 healthy controls (HCs) underwent resting-state functional magnetic resonance imaging. We compared the SN, DMN, and CEN connectivity patterns of the three groups. The role of the SN in networks with significant connectivity differences was examined by mediation analysis. RESULTS: FEP patients showed lower SN-DMN and SN-CEN (cluster-level F=5.83, false discovery rate [FDR] corrected-p=0.001) connectivity than HCs. There was lower SN-DMN connectivity (cluster-level F=3.06, FDR corrected-p=0.053) at a trend level in CHR subjects compared to HCs. Between HCs and FEP patients, mediation analysis showed that SN-DMN connectivity was a mediator between group and SN-CEN connectivity. Additionally, SN-CEN connectivity functioned as a mediator between group and SN-DMN connectivity. CONCLUSION: Aberrant connectivity between the SN and DMN/CEN suggests disrupted network switching in FEP patients, although CHR subjects showed trend-level SN-DMN dysconnectivity. Our findings suggest that dysfunctional triple-network dynamics centered on the SN can appear in patients in the early stages of psychotic disorders.
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Neuroimaging studies have revealed how intrinsic dysconnectivity among cortical regions of the mentalizing network (MENT) and the mirror neuron system (MNS) could explain the theory of mind (ToM) deficit in schizophrenia patients. However, despite the concurrent involvement of the cerebellum with the cortex in social cognition, the dysfunction in intrinsic interplay between the cerebellar nodes of MENT/MNS and the cortex in schizophrenia patients remains unknown. Thus, we aimed to investigate whether resting-state cerebello-cortical dysconnectivity exists in first-episode psychosis (FEP) patients in relationship with their ToM deficit. A total of 37 FEP patients and 80 healthy controls (HCs) underwent resting-state functional magnetic resonance imaging. Using a priori-defined cerebellar seeds that functionally connect to the MENT (right crus II) and MNS (right crus I), we compared cerebello-cortical functional connectivities (FCs) in FEP patients and HCs. Correlations between cerebello-parietal connectivities and ToM performance were investigated in FEP patients. FEP patients showed hyperconnectivity between the right crus II and anterior cingulate gyrus and between the right crus I and supplementary motor area, bilateral postcentral gyrus, and right central/parietal operculum (CO/PO). Hypoconnectivity was found between the right crus II and left supramarginal gyrus (SMG) in FEP patients. FCs between the right crus II and left SMG and between the right crus I and right CO/PO were significantly correlated with ToM scores in FEP patients. In accordance with the "cognitive dysmetria" hypothesis, our results highlight the importance of cerbello-cortical dysconnectivities in understanding social cognitive deficits in schizophrenia patients.
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The symptoms of obsessive-compulsive disorder (OCD) are largely related to impaired executive functioning due to frontostriatal dysfunction. To better treat OCD, the development of biomarkers to bridge the gap between the symptomatic-cognitive phenotype and brain abnormalities is warranted. Therefore, we aimed to identify biomarkers of impaired organizational strategies during visual encoding processes in OCD patients by developing an eye tracking-based Rey-Osterrieth complex figure test (RCFT). In 104 OCD patients and 114 healthy controls (HCs), eye movements were recorded during memorization of the RCFT figure, and organizational scores were evaluated. Kullback-Leibler divergence (KLD) scores were calculated to evaluate the distance between a participant's eye gaze distribution and a hypothetical uniform distribution within the RCFT figure. Narrower gaze distributions within the RCFT figure, which yielded higher KLD scores, indicated that the participant was more obsessed with detail and had less organizational strategy. The OCD patients showed lower organizational scores than the HCs. Although no group differences in KLD scores were noted, KLD scores were significantly associated with organization T scores in the OCD group. The current study findings suggest that eye tracking biomarkers of visual memory encoding provide a rapidly determined index of executive functioning, such as organizational strategies, in OCD patients.
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Biomarcadores , Função Executiva , Movimentos Oculares , Memória , Transtorno Obsessivo-Compulsivo/diagnóstico , Transtorno Obsessivo-Compulsivo/fisiopatologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Transtorno Obsessivo-Compulsivo/etiologia , Avaliação de Sintomas , Adulto JovemRESUMO
AIM: Although the thalamus is a key structure in the pathophysiology of obsessive-compulsive disorder (OCD), reports regarding thalamic volume alterations in OCD patients have been inconsistent. Because the thalamus has a complex structure with distinct functions, we investigated subregional volume changes in the thalamus and their relationship with clinical attributes in a large sample of medication-free OCD patients. METHODS: We collected T1-weighted magnetic resonance imaging data from 177 OCD patients and 152 healthy controls (HCs). Using FreeSurfer, we segmented the thalamus into 12 nuclei groups; subregional volumes were compared between groups using an analysis of covariance. The relationships between altered thalamic volumes and OC symptom severity and OCD onset age were investigated. RESULTS: Compared to HCs, OCD patients showed a smaller volume of the left posterior thalamic nuclei. Other thalamic subregions did not show significant group differences. There was a significant negative correlation between the volume of the left posterior thalamic nuclei and the age of OCD onset but no significant correlation with OC symptom severity. CONCLUSIONS: This is the first study to report reduced volume of the posterior thalamic nuclei in a large sample of medication-free OCD patients. Our results suggest that the volume of posterior thalamic nuclei may reflect different pathophysiological mechanisms of OCD subtypes related to the age of onset. Additional studies with pediatric samples are required to clarify the relationship between thalamic alterations and the onset age of OCD.
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Transtorno Obsessivo-Compulsivo , Núcleos Posteriores do Tálamo , Criança , Humanos , Imageamento por Ressonância Magnética , Transtorno Obsessivo-Compulsivo/diagnóstico por imagem , Tálamo/diagnóstico por imagemRESUMO
Functional neuroimaging studies have implicated alterations in frontostriatal and frontoparietal circuits in obsessive-compulsive disorder (OCD) during various tasks. To date, however, brain activation for visuospatial function in conjunction with symptoms in OCD has not been comprehensively evaluated. To elucidate the relationship between neural activity, cognitive function, and obsessive-compulsive symptoms, we investigated regional brain activation during the performance of a visuospatial task in patients with OCD using functional magnetic resonance imaging (fMRI). Seventeen medication-free patients with OCD and 21 age-, sex-, and IQ-matched healthy controls participated in this study. Functional magnetic resonance imaging data were obtained while the subjects performed a mental rotation (MR) task. Brain activation during the task was compared between the two groups using a two-sample t-test. Voxel-wise whole-brain multiple regression analyses were also performed to examine the relationship between obsessive-compulsive symptom severity and neural activity during the task. The two groups did not differ in MR task performance. Both groups also showed similar task-related activation patterns in frontoparietal regions with no significant differences. Activation in the right dorsolateral prefrontal cortex in patients with OCD during the MR task was positively associated with their total Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) scores. This study identified the specific brain areas associated with the interaction between symptom severity and visuospatial cognitive function during an MR task in medication-free patients with OCD. These findings may serve as potential neuromodulation targets for OCD treatment.
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Exploring the disruptions to intrinsic resting-state networks (RSNs) in schizophrenia-spectrum disorders yields a better understanding of the disease-specific pathophysiology. However, our knowledge of the neurobiological underpinnings of schizotypal personality disorders mostly relies on research on schizotypy or schizophrenia. This study aimed to investigate the RSN abnormalities of schizotypal personality disorder (SPD) and their clinical implications. Using resting-state data, the intra- and inter-network of the higher-order functional networks (default mode network, DMN; frontoparietal network, FPN; dorsal attention network, DAN; salience network, SN) were explored in 22 medication-free, community-dwelling, non-help seeking individuals diagnosed with SPD and 30 control individuals. Consequently, while there were no group differences in intra-network functional connectivity across DMN, FPN, DAN, and SN, the SPD participants exhibited attenuated anticorrelation between the right frontal eye field region of the DAN and the right posterior parietal cortex region of the FPN. The decreases in anticorrelation were correlated with increased cognitive-perceptual deficits and disorganization factors of the schizotypal personality questionnaire, as well as reduced independence-performance of the social functioning scale for all participants together. This study, which links SPD pathology and social functioning deficits, is the first evidence of impaired large-scale intrinsic brain networks in SPD.
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BACKGROUND: Emotion dysregulation is crucial to both poor social functioning and psychotic symptom formation in patients with schizophrenia. The efficient use of emotion regulation strategies, such as cognitive reappraisal, has been less frequently observed in the early phases of psychotic disorder. It is unknown whether neurophysiological responses related to emotion regulation by cognitive reappraisal are altered in early psychosis. METHODS: Fifty-four patients with first-episode psychosis (FEP), 34 subjects at clinical high risk (CHR) for psychosis, and 30 healthy controls (HCs) participated in event-related potential recordings during a validated emotion regulation paradigm to measure the effect of cognitive reappraisal on emotion regulation. Late positive potentials (LPPs), which reflect emotional arousal, were compared across the groups and the 3 conditions (negative, cognitive reappraisal, and neutral). The relationship among LPP modulation by cognitive reappraisal and social/role functioning and severity of psychotic symptoms was investigated in the early psychosis group. RESULTS: The FEP and CHR participants showed comparably larger LPP amplitudes in the negative and cognitive reappraisal conditions than in the neutral condition, whereas the HCs presented larger LPPs in the negative condition than in the cognitive reappraisal and neutral conditions. LPP modulation by cognitive reappraisal was negatively correlated with positive symptom severity in the FEP patients and with disorganization severity in the CHR subjects. CONCLUSIONS: Inefficient use of cognitive reappraisal may be related to the impaired emotion regulation and psychotic symptoms from the very beginning of psychotic disorder. This study provides the first neurophysiological evidence regarding current concepts of emotion regulation in early psychosis.
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Sintomas Afetivos/fisiopatologia , Regulação Emocional/fisiologia , Potenciais Evocados/fisiologia , Julgamento/fisiologia , Transtornos Psicóticos/fisiopatologia , Esquizofrenia/fisiopatologia , Percepção Social , Adolescente , Adulto , Sintomas Afetivos/etiologia , Suscetibilidade a Doenças , Eletroencefalografia , Humanos , Transtornos Psicóticos/complicações , Risco , Esquizofrenia/complicações , Adulto JovemRESUMO
Characterization of obsessive-compulsive disorder (OCD), like other psychiatric disorders, suffers from heterogeneities in its symptoms and therapeutic responses, and identification of more homogeneous subgroups may help to resolve the heterogeneity. We aimed to identify the OCD subgroups based on resting-state functional connectivity (rsFC) and to explore their differences in treatment responses via a multivariate approach. From the resting-state functional MRI data of 107 medication-free OCD patients and 110 healthy controls (HCs), we selected rsFC features, which discriminated OCD patients from HCs via support vector machine (SVM) analyses. With the selected brain features, we subdivided OCD patients into subgroups using hierarchical clustering analyses. We identified 35 rsFC features that achieved a high sensitivity (82.74%) and specificity (76.29%) in SVM analyses. The OCD patients were subdivided into two subgroups, which did not show significant differences in their demographic and clinical backgrounds. However, one of the OCD subgroups demonstrated more impaired rsFC that was involved either within the default mode network (DMN) or between DMN brain regions and other network regions. This subgroup also showed both lower improvements in symptom severity in the 16-week follow-up visit and lower responder percentage than the other subgroup. Our results highlight that not only abnormalities within the DMN but also aberrant rsFC between the DMN and other networks may contribute to the treatment response and support the importance of these neurobiological alterations in OCD patients. We suggest that abnormalities in these connectivity may play predictive biomarkers of treatment response, and aid to build more optimal treatment strategies.
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Mapeamento Encefálico , Transtorno Obsessivo-Compulsivo , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Transtorno Obsessivo-Compulsivo/diagnóstico por imagem , Transtorno Obsessivo-Compulsivo/terapiaRESUMO
Conservatives are more sensitive to threatening/anxious situations in perceptual and cognitive levels, experiencing emotional responses and stress, while liberals are more responsive to but tolerant of ambiguous and uncertain information. Interestingly, conservatives have greater psychological well-being and are more satisfied with their lives than liberals despite their psychological vulnerability to stress caused by threat and anxiety sensitivities. We investigated whether conservatives have greater resilience and self-regulation capacity, which are suggested to be psychological buffers that enhance psychological well-being, than liberals and moderates. We also explored associations between intrinsic functional brain organization and these psychological resources to expand our neurobiological understanding of self-regulatory processes in neuropolitics. We found that conservatives, compared to liberals and moderates, had greater psychological resilience and self-regulation capacity that were attributable to greater impulse control and causal reasoning. Stronger intrinsic connectivities between the orbitofrontal cortex (OFC) and precuneus and between the insula and frontal pole/OFC in conservatives were correlated with greater resilience and self-regulation capacity. These results suggest the neural underpinnings that may allow conservatives to manage the psychological stress and achieve greater life satisfaction. This study provides neuroscientific evidence for the different responses of liberals and conservatives to politically relevant social issues.
Assuntos
Atitude , Encéfalo/fisiologia , Rede Nervosa/fisiologia , Política , Resiliência Psicológica , Estresse Psicológico/psicologia , Feminino , Humanos , Masculino , Neurobiologia , Adulto JovemRESUMO
OBJECTIVE: It is well established that the cortico-striato-thalamo-cortical (CSTC) circuit is implicated in the pathophysiology of obsessive- compulsive disorder (OCD). However, reports on corticostriatal functional connectivity (FC) in OCD have been inconsistent due to the structural and functional heterogeneity of the striatum. Therefore, in the present study, we investigated corticostriatal FC using a fine 12-seed striatal parcellation to overcome this heterogeneity and discover the neural correlates of symptoms in OCD patients. METHODS: We recruited 23 OCD patients and 23 healthy controls (HCs). Whole-brain FC based on striatal seeds was examined using resting-state functional magnetic resonance imaging data and compared across OCD patients and HCs. We conducted correlation analysis between FCs of striatal subregions with significant group differences and symptom severity scores on the Yale-Brown Obsessive Compulsive Scale (Y-BOCS), Hamilton Rating Scale for Depression, and Hamilton Rating Scale for Anxiety (HAM-A). RESULTS: Compared to HCs, patients demonstrated increased FC of the dorsal caudal putamen and ventral rostral putamen (VRP) with several cortical regions, such as the intracalcarine cortex, inferior frontal gyrus, supramarginal/angular gyrus (SMG/AG), and postcentral gyrus (PCG). Furthermore, FC between the VRP and SMG/AG and between the VRP and PCG was negatively correlated with scores on the Y-BOCS compulsive subscale and the HAM-A, respectively. CONCLUSION: These findings suggest that striatal subregions have strengthened FC with extensive cortical regions, which may reflect neural correlates of compulsive and anxious symptoms in OCD patients. These results contribute to an improved understanding of OCD pathophysiology by complementing the current evidence regarding striatal FC.
RESUMO
BACKGROUND: Although cognitive dysfunction is a core element of schizophrenia, the neurobiological underpinnings of the pathophysiology are not yet sufficiently understood. Because the resting state is crucial for cognitive functioning and electroencephalography (EEG) can reflect instantaneous neural activity, we investigated theta phase-gamma amplitude coupling (TGC) of resting-state EEG and its relationship with cognitive function in patients with first-episode psychosis (FEP) to reveal the neural correlates of cognitive dysfunction. METHODS: A total of 59 FEP patients and 50 healthy controls (HCs) underwent resting-state, eyes-closed EEG recordings and performed the Trail Making Test Part A (TMT-A) and Part B (TMT-B) and California Verbal Learning Test (CVLT). TGC from the source signal of the resting-state EEG in default mode network (DMN)-related brain regions was compared between groups. Correlation analyses were performed between TGC and cognitive function test performance in FEP patients. RESULTS: Mean resting-state TGC was larger for the FEP patients than for the HCs. Patients with FEP showed increased TGC in the left posterior cingulate cortex, which was correlated with better performance on the TMT-A and TMT-B and on immediate and delayed recall in the CVLT. CONCLUSIONS: These results suggest that patients with FEP show compensatory hyperactivation of resting-state TGC in DMN-related brain regions, which may be related to the reallocation of cognitive resources to prepare for successful cognitive execution. This study not only highlights the neural underpinnings of cognitive dysfunction in FEP patients but also provides useful background to support the development of treatments for cognitive dysfunction in schizophrenia.